Hedge shears



y 2, 1967 J. MIHALYI 3,316,638

HEDGE SHEARS Filed Sept. 2, 1965 JOSEPH M/HALY/ IN V EN TOR.

AGE/VT United States Patent Ofitice 3,316,638 HEDGE SHEARS Joseph Mihalyi, 76 Van Voorhis Ave, Rochester, N31. 14617 Filed Sept. 2, 1965, Ser. No. 484,601 9 Claims. (Cl. 30-262) The present invention relates to shears, such as hedge shears, and more particularly to an improved pivotal structure for such shears whereby the cutting edges of the blades are maintained in contact during operation of the shears, thereby automatically increasing the cutting action of the blades.

It is well known in many types of shears to provide means for maintaining the cutting blades in contact at all times as one or both blades are moved with respect to each other, so that a cutting action is maintained throughout the length of the blades. In known types of shears, such means comprises a nut on a pivotal stud with a strong tension spring positioned under the nut to force and maintain the blades in close and tight contact to insure a good cutting action. With such an arrangement, the tension spring permits one blade to move axially along the pivotal axis as one blade is moved relative to the other, in the event an uncuttable foreign object is encountered by the blades. With a shear, or shears, of this type, a part of the operating force applied to the handles is used to overcome the force exerted against the blades by the spring tension, so that a force greater than required as a normal operating force is necessary to actuate the shears even to'merely open and/or close the blades.

The disadvantages of those shears, which form the prior art, are overcome by the hedge shears disclosed and described in the present application. In the present invention, a relatively simple, pivotal structure is provided for the blades which permits all of the force applied to the movable arms to be used for moving the blades to provide a normal cutting action. The pivotal arrangement comprises a stud having one end thereof rotatably secured to an intermediate portion of one blade element for providing one axis about which the blades are moved, the stud extending through a hole in the intermediate portion of the other blade element. A member on the intermediate portion of the other blade is pivotally mounted in the stud for moving about another axis that is displaced from the blades and which extends in a direction corresponding substantially to that of the blade and the operating handle. Normally, the blades pivot about the stud as the blades are opened and closed by the operating handles,

An increased cutting action is obtained when an additional force is applied to the handle for the other blade. Such force causes the other blade to pivot about the other axis which is in a plane above the cutting plane, and be cause the handle is substantially below the plane of the other axis, its blade is urged into more intimate contact with the cutting edge of the one blade, thereby increasing the cutting action.

One of the primary objects of the invention is to provide a pivotal structure for the cutting blades of a shears which provides an optimum cutting action with a minimum operating force.

Another object of the invention is to provide a shears having a pivotal axis about which both blades can be moved and a pivotal axis at right angles to the first-mentioned axis and displaced from the cutting plane about which one of the blades can be moved so that its cutting edge is urged into more intimate contact with the cutting edge of the other blade to provide an absolute cutting action only on closing of the blades.

And yet another object of the invention is to provide 3,3 lti,638 Patented May 2, 1967 a pivotal structure that is simple in construction, that comprises only a few parts and that is relatively inexpensive in cost.

These and other objects and advantages of the invention will be readily apparent to those skilled in the art by the following description of a preferred embodiment of the invention,

Reference is now made to the accompanying drawing wherein like reference numerals designate like parts and wherein:

FIG. 1 is a perspective view of a hedge shears showing a pivotal arrangement for the blade elements in accord ance with the invention;

FIG. 2 is a side elevational view of the shears shown in FIG. 1 with the pivotal arrangement shown in cross section;

FIG. 3 is a vertical section taken substantially along the line 3-3 in FIG. 2;

FIG. 4 is a partial plan view of the blade-locking arrangement shown in FIG. 3;

FIG, 5 is a partial sectional view 55 in FIG. 4; and

FIG. 6 is a partial perspective view of one of the blades showing a gripping plate that is arranged at the inner end of the blade adjacent the pivotal axis.

With reference to FIG. 1, a shears generally designated by the numeral 11) comprises two movable blade elements designated by the numerals 11 and 12. The blade element 11 comprises a concave cutting blade 13 that is fixed to an extension 14 of an intermediate portion 15, for example, by means of a number of rivets 16. The intermediate portion 15 carries a tubular handle 17 that extends therefrom in a direction opposite to that of the blade 13 and is substantially aligned with the latter. The handle 17 can be provided with a rubber hand grip 18, as seen in FIG. 1. The blade element 12 comprises a convex cutting blade 21 which is secured to an extension 22 of an intermediate portion 23, for example, by means of a plurality of rivets 24. The intermediate portion 23 also carries a tubular handle 25 that extends therefrom in a direction opposite to that of the blade 21 and can be provided with a rubber hand grip 26.

As seen in FIG. 2, the intermediate portion 23 carries a stud 28 that is rotatably mounted and retained thereon by means of a nut 29 that threadedly engages an end 3d of the stud, The stud 23 extends through an aperture 31 in intermediate portion 15 and is provided at its end 32 with a diametrical bore or hole 33.

The intermediate portion 15 carries a pair of spaced upright members 35 and 36, the latter being arranged on opposite sides of the aperture 31 and aligned substantially with the blade 13 and handle 17. A pin 37 that is carried by the members 35, 36 is rotatably received by the hole 33 in stud 28, see FIG. 3.

With reference again to FIG. 1, it will be noted that the blade elements 11 and 12 are arranged in an overlapped relationship so that upon movement of handles 17 and 25 toward and away from each other the blades 13 and 21 are pivoted about stud 28 and moved across each other progressively to provide the cutting action. The relationship of the elements 11 and 12 is maintained by the pin 37 and stud 28 so that for normal cutting action the same pressure is always exerted along the cutting edges 38, 39 of the blades. As shown in FIGS. 1 and 3, the aperture 31 in intermediate portion 15 is larger than the diameter of stud 28. This is made in this way so that the cutting edges 38, 39 of the blade elements 11 and 12 can be pivoted toward one another, either singly or together, to provide continuous contact of the cutting edges, thereby increasing the cutting action between blades 13 and 21.

While the elements 11 and 12 are shown as having an taken along the line '5 .s angular formation, as seen in FIG. 2, the structure and function of the pivotal arrangement comprising stud 2S and pin 37 is such that the same action can be obtained even when the blades 13, 21 intermediate portions 15, 23 and handles 17, 25 are respectively arranged in substantially the same plane. The angular relationship of the elements as shown in FIG. 2 is provided to permit holding the elements 11 and 12 in a position that facilitates ease of operation and automatically increases the cut-ting action.

As seen in FIGS. 1 and 2, the axis B of pin 37 forms an acute angle A with the cutting plane C through which the cut-ting edges 38 and 39 are moved. Also, the handles 18 and 2 6 are ar-ranged below the axis B and extend below the cutting plane C. Accordingly, when the cutting edges 38 and 39 encounter the material to be cut, the additional force applied to handles 17 and 25 to move the blades into a closed position and cut the material automatic-ally causes an increased cutting action because the additional force on handle 17 is converted, in effect, to a torque force which causes blade 13 to pivot and move toward blade 21, thereby bringing the cutting edges 38 and 39 into more intimate contact to accomplish the cutting of the material.

Means for holding the elements 11 and 12 in a closed position is shown in FIGS. 1, 4 and 5. The intermediate portion is provided on the right-hand side, as viewed in FIGS. 1 and 4, with an extension 40 that has an indentation 41 for receiving the formed-down nose 42 of a manually-operable holding member 43. The holding member 43 is pivotally mounted on a stud 44 that is secured to an extension 45 of the intermediate portion 23. The member 43 is held in a position spaced from intermediate portion 23 by a sleeve 46, as shown in FIG. 5, which is preferably formed of rubber or a similar resilient material. An edge 47 of control portion 15 engages sleeve 46 to limit the open position of blades 13 and 21. Likewise, an edge 48 of extension 40 engages sleeve 46, see FIG. 4, when the blades are in a closed position. When the elements 11 and 12 are in a closed position, the member 43 can be moved about stud 44 so that the nose 42 engages the indentation 41, thereby holding the elements 11 and 12 in a closed position. The member 43 is moved in a reverse direction to release the nose 42 so that the elements 11 and 12 can be moved relative to each other to provide a shearing action.

In FIG. 6, a plate 50 having a serrated edge 51 is shown as being secured between the cutting blade 21 and the extension 22. The plate 50 is arranged over extension 22 so that in a fully-opened position a relatively large twig or branch can be held by the edge 51. The cutting action therefore takes place at the innermost edges of the cutting blades 13, 21 and in close proximity to the pivotal axis defined by stud 28 so that a maximum cutting force can be exerted.

In a preferred embodiment of the shears structure described above, the cutting blades 13 and 21 are preferably made of a thin metal which has suflicient rigidity so that one blade can be formed with a convex cross section throughout its length and the other blade can be formed with a concave cross section throughout its length. With this configuration, the cutting edges 38 and 39 are forced into intimate contact as the blades are moved progressively across each other by the handles 17 and which are operated and moved in corresponding directions. By making the cutting blades 13 and 21 of thin metal, the weight of the shears is reduced considerably without detracting from the rigidity of the blades and the cutting action.

As shown in FIG. 1, the intermediate portions 15 and 23 receive the cutting blades and handles to provide a unitary element. However, it is conceivable that the blade, intermediate portion and handle of each of ele ments 11 and 12 can be formed as a single member without departing from the principle of the invention nor in- A fluencing the cutting action obtained by the pivotal arrangement described above. While the axis of stud 28 and the axis of pin 37 are shown as being at right angles to each other with the axis of pin 37 arranged above the intermediate portion 15, the same action can be accomplished by inversion of the parts. Likewise, this same pivotal relationship can be obtained by structures other than that disclosed and described above.

The invention has been described in detail with particular reference to a preferred embodiment thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention as described hereinabove and as defined in the appended claims.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A pivotal arrangement for shears comprising a first movable member having an intermediate portion from which a cutting blade and a handle extend in opposite directions along substantially the same line, and a second movable member having an intermediate portion from which a cutting blade and a handle extend in opposite directions along substantially the same line, said first and second movable members being arranged in an overlapped relation, the combination comprising:

first pivot means rotatably mounted in one of said intermediate portions and extending through an aperture in the other of said intermediate portions for establishing a first axis that is substantially perpendicular to said intermediate portions and about which said cutting blades are moved across each other progressively by said handles as the latter are moved toward each other from an open position to a closed position; and second pivot means fixedly mounted on the other of said intermediate portions and rotatably coupled to said first pivot means for establishing a second axis that intersects said first axis substantially perpendicular thereto and is spaced from and substantially parallel to the line of extension of said handle and cutting blade on said other intermediate portion;

said second pivot means rotating said first pivot means as said handles are moved between said open and closed positions and permitting said cutting blade extending from said other intermediate portion to be pivot-ally urged about said second axis and toward the cutting blade extending from said one intermediate portion for increasing the cutting action of said blades.

2. A pivotal arrangement in accordance with claim 1 wherein said first pivot means comprises a stud having one end thereof extending through said aperture in said other intermediate portion, said other end being provided with a diametrical hole having an axis that is substantially perpendicular to the axis of said stud and lies in a plane spaced from and substantially parallel to that of said other intermediate portion.

3. A pivotal arrangement in accordance with claim 1 wherein said second pivot means comprises a member on said other intermediate portion adjacent said aperture and including an axial member extending across and spaced from said aperture and journaled in said first pivot means for supporting said second movable member in said overlapped relation to said first movable member.

4. A pivotal arrangement in accordance with claim 1 including a lug on one of said intermediate portions and a releasable engaging member in the other of said intermediate portions for locking said first and second movable members together when said handles are in said closed position.

5. A pivotal arrangement for shears comprising a first movable member having an intermediate portion from which a cutting blade and a handle extend in opposite direction along substantially the same line, and a second movable member having an intermediate portion from which a cutting blade and a handle extend in opposite directions along substantially the same line, said first and second movable members being arranged in an overlapped relation, the combination comprising:

a stud having one end thereof rotatably secured to one of said intermediate portions and the other end thereof extending through an aperture in the other of said intermediate portions, said other end being provided with a diametrical hole having an axis that is substantially perpendicular to the axis of said stud and lies in a plane spaced from and substantially parallel to that of said other intermediate portion; and

a member on said other intermediate portion adjacent said aperture and including an axial member extending across and spaced from said aperture and journaled in said diametrical hole for supporting one of said movable members in said overlapped relation to the other of said movable members;

said cutting blades being movable in a cutting plane by said handles about the axis of said stud and across each other between an open and a closed position; and

said cutting blade extending from said other intermediate portion being movable by its respective handle about the axis of said diametrical hole for urging said blades into more intimate contact to increase the cutting action thereof.

6. A pivotal arrangement in accordance with claim 5 including a lug on one of said intermediate portions and a releasable pivotal member on the other of said intermediate portions for engaging said lug to lock said first and second movable members together when said handles are in said closed position.

7. A pivotal arrangement in accordance with claim 5 wherein the axis of said axial member is arranged at an acute angle to said cutting plane.

8. A pivotal arrangement in accordance with claim 5 wherein said handles are displaced from the axis of said axial member.

9. A pivotal arrangement in accordance with claim 5 wherein said handles are displaced in the same direction from the axis of said axial member and from said cutting plane. 

1. A PIVOTAL ARRANGEMENT FOR SHEARS COMPRISING A FIRST MOVABLE MEMBER HAVING AN INTERMEDIATE PORTION FROM WHICH A CUTTING BLADE AND A HANDLE EXTEND IN OPPOSITE DIRECTIONS ALONG SUBSTANTIALLY THE SAME LINE, AND A SECOND MOVABLE MEMBER HAVING AN INTERMEDIATE PORTION FROM WHICH A CUTTING BLADE AND A HANDLE EXTEND IN OPPOSITE DIRECTIONS ALONG SUBSTANTIALLY THE SAME LINE, SAID FIRST AND SECOND MOVABLE MEMBERS BEING ARRANGED IN AN OVERLAPPED RELATION, THE COMBINATION COMPRISING: FIRST PIVOT MEANS ROTATABLY MOUNTED IN ONE OF SAID INTERMEDIATE PORTIONS AND EXTENDING THROUGH AN APERTURE IN THE OTHER OF SAID INTERMEDIATE PORTIONS FOR ESTABLISHING A FIRST AXIS THAT IS SUBSTANTIALLY PERPENDICULAR TO SAID INTERMEDIATE PORTIONS AND ABOUT WHICH SAID CUTTING BLADES ARE MOVED ACROSS EACH OTHER PROGRESSIVELY BY SAID HANDLES AS THE LATTER ARE MOVED TOWARD EACH OTHER FROM AN OPEN POSITION TO A CLOSED POSITION; AND SECOND PIVOT MEANS FIXEDLY MOUNTED ON THE OTHER OF SAID INTERMEDIATE PORTIONS AND ROTATABLY COUPLED TO SAID FIRST PIVOT MEANS FOR ESTABLISHING A SECOND AXIS THAT INTERSECTS SAID FIRST AXIS SUBSTANTIALLY PERPENDICULAR THERETO AND IS SPACED FROM AND SUBSTANTIALLY PARALLEL TO THE LINE OF EXTENSION OF SAID HANDLE AND CUTTING BLADE ON SAID OTHER INTERMEDIATE PORTION; SAID SECOND PIVOT MEANS ROTATING SAID FIRST PIVOT MEANS AS SAID HANDLES ARE MOVED BETWEEN SAID OPEN AND CLOSED POSITIONS AND PERMITTING SAID CUTTING BLADE EXTENDING FROM SAID OTHER INTERMEDIATE PORTION TO BE PIVOTALLY URGED ABOUT SAID SECOND AXIS AND TOWARD THE CUTTING BLADE EXTENDING FROM SAID ONE INTERMEDIATE PORTION FOR INCREASING THE CUTTING ACTION OF SAID BLADES. 